Known reconfiguration techniques include techniques addressing reconfiguration at the connection level and techniques addressing reconfiguration at the link level. For example, at the connection level, M. T. Frederick, P. Datta and A. K. Somani, “Sub-graph Routing a Generalized Fault-tolerant Strategy for Link Failures in WDM Optical Networks,” Computer Networks, vol. 50, pp. 181-199 (2005), discloses pre-computing the backup path of connections for each possible link failure by filtering out a subset of links. S. Ramasubramanian, “On Failure Dependent Protection in Optical Grooming Networks,” Dependable Systems and Networks (2004), presents a method for pre-computing multiple failure dependent backups for each end-to-end primary path. J. Zhang, K. Zhu, and B. Mukherjee, “Backup Reprovisioning to Remedy the Effect of Multiple Link Failures in WDM Mesh Networks,” IEEE JSAC, vol. 24, no. 8 (August 2006), presents an Integer Linear Program (ILP) and heuristic solutions for re-provisioning backup paths that became vulnerable because of a failure at the end-to-end connection level.
Reconfiguration techniques addressing reconfiguration at the link level have also been proposed. The primary motivation for reconfiguration in A. Kvalbein, Tarik C., and S. Gjessing, “Post-Failure Routing Performance with Multiple Routing Configurations,” IEEE INFOCOM (2007), is load-balancing, instead of protecting against subsequent failures. S. Kim, and S. S. Lumetta, “Evaluation of Protection Reconfiguration for Multiple Failures in Optical Networks,” OFC 2003, evaluates the benefits of reconfiguration in the WDM layer. That paper considers both link-level and connection-level reconfiguration, but the evaluation is based on unit capacity demands. H. Choi, S. Subramaniam, and H. Choi, “On double-link failure recovery in WDM optical networks,” IEEE INFOCOM (2002), proposes a restricted type of reconfiguration where any failed link in a backup path is replaced by its backup path. Those authors formulate and solve the problem of computing a set of initial backup paths such that this reconfiguration process succeeds for most double failures.
There remains a need to address the cross-layer reconfiguration of impacted backup paths using Open Shortest Path First (OSPF)-Traffic Engineering (TE) and Resource Reservation Protocol (RSVP) for surviving multiple failures with a simple distributed protocol. The inventors disclose such a technique herein, and demonstrate its efficacy on large carrier-class network topologies with realistic demands.